Liquid Chromatography-Mass Spectrometry (LC-MS) has seen enormous growth in clinical laboratories during the last few years. It offers specificity superior to that of immunoassays and other conventional methods. The LC-MS technology has many advantages and has penetrated from the referral laboratories to even the smaller laboratories. Techniques that improve throughput include direct sample injection, LC-multiplexing, and sample multiplexing. Measures to improve specificity and sensitivity include sample clean-up and optimizing chromatography to avoid interferences and ion suppression due to sample-matrix components. Next-generation instrumentation may offer additional benefits. LC Mass spectrometry, which has been around for hundred years, has its basic principles rooted in the concept of separation of a stream of ionized neon gas into two isotopic components by applying a magnetic and electric field to it.
Mass Spectrometry and clinical use of LC-MS/MS analysis underwent rapid technical developments and became a widely used analytical technique in the physical and chemical sciences and have seen unprecedented growth during the last 10 to 15 years. LC-MS/MS combines high analytical specificity with high analytical sensitivity, allowing for a significantly low cost of use compared with the alternative techniques. LC-MS technique has a broad spectrum of clinical benefits and allows for an easier workflow and higher throughput than the conventional hplc or GC-MS methods.
Applications
Primary Aldosteronism
Aldosterone measurement is performed to confirm autonomous aldosterone secretion by an adrenal tumor (primary aldosteronism), which is one of the more common causes of potentially curable secondary arterial hypertension. Accurately measuring circulating aldosterone concentrations is essential for the correct diagnosis of hyperaldosteronism. The lc ms method provides accurate and specific data with concentrated and enhanced sensitivity.
Cortisol Measurements and Cushing’s Syndrome
Cushing’s syndrome most commonly affects ages 20 to 50. It is a relatively rare hormonal disorder caused by prolonged exposure of the body’s tissues to high cortisol levels. No single laboratory test is perfect for diagnosis; several tests usually need to be performed, most of which are centered on cortisol measurements. LC-MS/MS reduces the labor requirements and decreases the potential for human error.LC-MS/MS has transformed into an affordable, flexible and accessible technique and has helped develop routine methods of high sensitivity and specificity, providing increased efficiency. These novel methods have positively impacted patient care on both economic and quality fronts.Clinical laboratories embraced LC-MS/MS lab within them because it combined high detection sensitivity with high analyte specificity when used in MRM mode. It offers all the advantages of GC-MS without the disadvantages of compromised detection sensitivity and long chromatography run-times. Clinical LC-MS/MS, in its relatively straightforward configuration of triple quadrupole LC-MS/MS, has seen incredible success and growth for many low molecular weight analytes during the past 10–15 years. It has quickly expanded into endocrine testing from initial use in biochemical genetics and newborn screening to drug and toxicology testing. It now forms the mainstay of referral steroid and biogenic amine testing, capable of high sensitivity and specificity in quantifying these analytes in large numbers of patient samples. We can expect this field to grow in scope and importance exponentially.
